block 2 lecture 8 Flashcards
what is alveolar ventilation?
amount of gas involved in gas exchange
IRV?
inspiratory reserve volume
TV?
tidal volume
ERV?
expiratory reserve volume
TLC?
total lung capacity
ic?
inspiratoty volume
RV?
residual volume
FRC?
functional residual capacity
VC?
vital capacity
what can be used to measure RV and FRC?
spirometer
when do you get increased inspiratory volume?
emphysema and COPD
what is FEV1 used to measure?
asthma
COPD
airway obstruction
what is the driving force for gas transport?
preasure gradient
what stops the lungs collapsing in?
pleura is attatched to the chest wall
what happens when you expand the chest cavity?
pressure becomes negative so air comes in as it is lower than outside
whats more soluble out of CO2 and O2?
CO2
what is the diffusion capacity?
ability of gas to travel across alveoli
what is the arterial oxygen conc?
amount bound to heamoglobin and dissolved in the plasma
formation of haemoglobin?
Haemoglobin has 3D shape there are 2 alpha and 2 beta chains, with a heam group and 2 porphyry rings
what state is iron in in haemoglobin?
ferrous
what causes the oxygen dissociation curve to shift to the right?
increased hydrogenn ions
increased CO2
increased temperature
increased BPG
what is the right hand shift called?
Bohr shift
what different about foetal haemoglobin?
gamma chains instead of beta
what happens to the oxygen dissociation curve with fetal haemoglobin?
shifts to the left as there is a higher affinity
what forms when carbon dioxide binds to haemoglobin?
carbamino haemoglobin
ways of carbon dioxide transport?
bound to haemoblobin
dissolved in plasma
bicarbonate
what acts as a buffer for hydrogen ions?
deoxyhaemoglobin
what happens with hyperventilation?
low CO2
hypocapnia
alkaline blood
hypoventilation?
high CO2
hypercapnia
acidic blood
in diabetic ketoacidosis what happens to the blood?
acidic blood
what does renal failure result in?
acidosis
what happens if you take lots of antacids?
alkalosis
what is buffering of the blood done by?
haemoglobin
blood protein
bicarbonate ions